Cognitive radio will demand fully tunable front end RF systems on mobile devices such as mobile phones, PDAs and netbook computers. This project studies methods of attaining a tuned antenna system operating over multiple frequency bands from 100 MHz p to 6 GHz. Two approached have been adopted. The first examined the use of liquid crystal dielectrics tuned by a voltage applied across the surface.
This resulted in changes in the dielectric constant and a tuning range of up to 8%. The second method has used MEMs switches to reconfigure the antenna and a third method varactor diodes in a matching circuit. Some results are given below. This project is supported by Antenova.